//顺序查找
#pragma once
//在数组a[n]中查找x顺序查找
//若找到返回下标，否则返回-1
template <typename E>
int SqSearch(E a[], int n, E x)
{
    for (int i = 0; i < n; i++)
        if (a[i] == x)
            return i;
    return -1; // not found
}